That seems like a huge amount of money for very little. One of my other interests apart from sailing is building and flying radio controlled model aircraft ( when I say "flying" I really mean crashing). These days, most of us use electric power via Lipo ( lithium polymer) batteries, and one of my fellow aviators has diabetes, and failing eyesight because of it. He has been forbidden to drive, so has rigged up an electric bicycle using a model aircraft electric motor, and lipo batteries. I have clocked him doing 30 mph and he says the duration is good. He is quite a whizz at things mechanical and electrical, and I am sure he could put together an electric outboard for a fraction of the prices I have been seeing on this forum. I think the main problem would be keeping the motor from the water, as I think the easiest way is with direct drive from a motor under the surface. Since lockdown, we have not been able to get together for flying/crashing, so I have not seen him for a while, but might be able to contact him if anyone thought it were a good idea. I am thinking of the possibility of making electric Swallow propulsion actually realistic from an economical point of view. Any thoughts ?